全文获取类型
收费全文 | 8455篇 |
免费 | 325篇 |
出版年
2020年 | 109篇 |
2019年 | 156篇 |
2018年 | 188篇 |
2017年 | 211篇 |
2016年 | 267篇 |
2015年 | 191篇 |
2014年 | 173篇 |
2013年 | 2548篇 |
2012年 | 239篇 |
2011年 | 258篇 |
2010年 | 286篇 |
2009年 | 250篇 |
2008年 | 223篇 |
2007年 | 241篇 |
2006年 | 240篇 |
2005年 | 119篇 |
2004年 | 118篇 |
2003年 | 108篇 |
2002年 | 111篇 |
2001年 | 124篇 |
2000年 | 87篇 |
1999年 | 108篇 |
1998年 | 76篇 |
1997年 | 61篇 |
1996年 | 75篇 |
1995年 | 85篇 |
1994年 | 81篇 |
1993年 | 86篇 |
1992年 | 78篇 |
1991年 | 64篇 |
1990年 | 60篇 |
1989年 | 76篇 |
1988年 | 66篇 |
1987年 | 78篇 |
1986年 | 74篇 |
1985年 | 88篇 |
1984年 | 75篇 |
1983年 | 99篇 |
1982年 | 79篇 |
1981年 | 83篇 |
1980年 | 77篇 |
1979年 | 73篇 |
1978年 | 78篇 |
1977年 | 67篇 |
1976年 | 76篇 |
1975年 | 72篇 |
1974年 | 56篇 |
1973年 | 59篇 |
1972年 | 64篇 |
1970年 | 49篇 |
排序方式: 共有8780条查询结果,搜索用时 31 毫秒
131.
132.
133.
134.
135.
136.
137.
Ashok V. Desai 《Development and change》1990,21(4):723-749
This paper analyses the results of a survey of twenty-four recent cases of technology imports into India. Over the last thirty years, large firms in Indian industry have come under increasing competitive pressure from small firms which pay lower wages and which are also favoured by government policy. Most small firms obtain technology through informal channels within the country. But some import technology; and larger firms import it in their defence against competition from small firms. Larger firms, with a history and a reputation, have better access to technology from abroad; smaller firms often go through an extensive search before they find a willing technology supplier. Irrespective of size, firms that import technology within their own specialization are observed to put more effort into technology choice, absorption and adaptation. Indian policies of across-the-board import substitution, by promoting diversification into new products developed abroad, tend to discourage specialization and hence to encourage technology imports and to work against technology absorption and innovation. 相似文献
138.
139.
Evans AW 《Journal of regional science》1990,30(4):515-531
"This paper questions the plausibility of the assumption of interregional equilibrium in recent research into migration and the valuation of amenities in the United States. It is shown that it is difficult to develop a satisfactory explanation for continuing net migration which is compatible with the equilibrium assumption, and that recent relevant research generally fails to support the idea that the U.S. economy is in equilibrium. The association of higher rent levels with in-migration is explained as a short-run phenomenon. If the spatial economy is in disequilibrium, then the valuations of amenities assuming equilibrium will be biased, being probably too low in areas of net in-migration and too high in areas of net out-migration." 相似文献
140.